1. Field of the Invention
The present invention relates to wearable display apparatuses.
2. Description of the Related Art
Microdisplays such as the ones used in head-mounted systems generally include a liquid crystal panel, and an illuminating device that irradiates light onto the liquid crystal panel. The liquid crystal panel can modulate the incident light to produce an image, which is then transferred through optics for display to the user's eye.
According to one known approach, the microdisplay can form a color image by using white light that illuminates color filters provided on the liquid crystal panel. However, this approach requires at least 3 color filtered sub-pixels per pixel, and thus is generally at least 3 times larger in size. As a result, microdisplays using color filters generally require larger optics, and display poor color quality due to electrical interaction between the color filtered sub-pixels.
Another known approach consists in using a field sequential color display technique to provide improved display performance and reduce the size of the microdisplay. According to the field sequential color display, a color image is divided into color fields based on the primary colors of red, green, and blue. As each color field is individually imaged by the microdisplay, the corresponding color light source is turned on. When these color fields are displayed in rapid sequence, a full color image can be perceived by a user. Because field sequential color display requires using multiple light sources (i.e., of different colors) that are spatially distinct, one encountered problem is that the illuminating light may not be uniformly distributed, i.e., the spatial distribution of each color light illuminating the light modulator may differ owing to the different location of the corresponding light source.
Therefore, there is a need for an improved wearable display apparatus that can address at least the foregoing issues.